Incinerating furnace



March 3, 1936. J. E. GREENAWALT INCINERATING FURNACE Original Filed Oct.28, 1953 2 Sheets-Sheet l Arroz/Vif March 3, 1936. J, E GREENAWALT2,032,412

INCINERATING FURNACE Original Filedct. 28, 1953 2 Shee'bs--Shee'l 2HTTOEIVEK Patented Mu.- 3, 1936 UNITED STATES 2,032,412 INCINERATINGFURNACE John E. Greenawalt, New York, N. Y.

Application october 2s, 193s, serial No. 695,631

Renewed August 9, 1935 8 Claims. (Cl. 110-15) My invention has relationto improvements in incinerating furnaces and the method practicedtherein, and it consists in the novel features of construction morefully set forth in the speciilcation and pointed out in the claims.

The present furnace is similar to that of my co-pending application,Serial No. 544,973, filed June 17, 1931, in that it is particularlyadapted for the burning of refuse including garbage which is charged onan air pervious support and caused to travel through the combustionchamber of the furnace, but in addition to the advantages of the furnaceof said application the furnace forming the subject-matter of thisapplication embodies improvements to expedite the ignition of thematerial and thus insure a longer burning period thereof as the materialmoves through said combustion chamber. These improvements include meansfor dividing the combustion chamber into zones through which thematerial passes successively, the primary zone being subject to a. downdraft of the gases from the secondary zone under the influence of air orother supporter of combustion moving upwardly through the supportand'material thereon. Thel advantage of the opposing drafts in thecombustion chamber is the retarding of the movement of the flamingparticles and hot gases that serve to ignite the material in order thatthey may be momentarily concentrated in the region of ignition so astoeffect such ignition. In order to effect this result an ignitingfurnace, or equivalent device, is so disposed that the ignition gasescoming therefrom will be effective on the material between the zones inlthe combustion chamber above mentioned. The advantage of thisarrangement, as well as other advantages incident thereto, will bebetter apparent from a detailed description of the invention inconnection with the accompanying drawings, in which:

Figure 1 is a top plan of my improved incinerating furnace with partsbroken away; Fig. 2 is a vertical longitudinal section taken through amedial plane and indicated by the line 2 2 of Fig. 1; Fig. 3 is avertical cross-section through the furnace taken on a plane indicated bythe zig-zag line 3--3 of Fig. 2; and Fig. 4 is a vertical cross-sectiontaken through the furnace on a plane indicated by the line 4-4 of Fig.2.

Referring to the drawings, I,. I represents the side walls of thefurnace sui-mounted by the arched roof 2, said walls and roof enclosingalong tunnel-like combustion chamber C. 4The furnace walls are carriedby-longltudinally extending angle bars 3, 3 structurally secured to thevertical angle bars 4, 4 equally spaced along the sides of the furnacewall and also serving as buck-stays for the furnace. Bracket members 5,5 are secured to the bottom flanges of angle bars 3, 3 and w help tocarry said walls. Opposite buck-stays 4,

4 are connected at the top by angle bars 6, and

the buck-stays on each side of the furnace are maintained in spacedrelation by channels 1. Thus, the walls I, I and furnace roof 2 whichtogether constitute the upper section of the furnace are carried by theangle bars 4, 4 through the brackets 5, 5 beneath which the travelingsection A of the furnace operates.

The traveling section A of the furnace operates immediately belowbrackets 5, 5. Said section A operates in intimate relation withlongitudinally extending channels 9, 9 below the brackets 5, 5 andspaced therefrom, said channels being carried by a series of angle barsIll extending between opposite buck-stays 4, 4 and secured thereto.

The combustion chamber C is divided into two zones by disposing the partof the roof 2. at the feed end of the furnace considerably lower thanthe main roof 2 and dropping down from the inner end of the oof sectionla baffle b. The zone z below the roof section 2', while a part of thecombustion chamber C, acts primarily for preheating the charge prior tocombustion, while the zone z' serves as the combustion chamber properwherein the combustion of the material proceeds for the purpose ofcompletely incinerating the same. At the forward end of the zone z is afeed hopper H for receiving the more finely divided material of gradedsize, and above the rearward end of the zone e, and utiliziing aplatform portion 8 of the roof 2' as a support for the material, is asecond hopper H' wherein the coarser, ungraded material is charged.Below the hopper H' there is constructed a suitable throat I I throughwhich the material feeds from the hopper, said throat having a dischargeopening I2leading into the combustion chamber zone z', and an opening I3opposite thereto through which operates a hollow rectangular plunger I4secured to the end of a piston I5 operable in cylinder I6 of a hydraulicram. The construction of the ram forms no part of the present inventionand, therefore, will not be described in detail, but let it beunderstood that it follows the conventional arrangement of devices ofthis kind in that it may be operated either by water or oil under thecontrol of properly located andl actuated valve mechanism. The functionof the ram is to carry the plungerA I4 through the throat II of thehopper and thereby eject material therefrom and feed the same into thecombustion chamber C. In its operation the top plate of the plunger I4serves to support the material m' as it moves through the hopper on itsforward stroke, the bottom plate riding on the platform 8 andthe endWall, obviously, ejecting the material from the hopper throat. Thehopper H is of conventional form and has its outlet I1 at the bottom soas to discharge the material onto the moving support (about to bedescribed) whereby it is carried into the zone 2. The moving support forthe material comprises a series of pallets I9, the side walls 20, 29 ofwhich are connected by cross bars 2I, said pallets also being providedwith suitable grates G, which form the air pervious supporting surfacefor the charge of material. The construction of the pallets and theconstruction of the'grates is immaterial as far as the present inventionis concerned and will, therefore, not be described in detail. However,adjacent pallets are interconnected through bars 22 at which points theyhavefree hinge movement so that they may travel around the end sprocketwheels 23 and 2l as an endless conveyor. The chain of pallets are drivenby a motor M directly connected with shaft 26 on which sprocket 24 ismounted. An air-box 26, supported by suitable structural members 21, isimmediately beneath the pallets I9 and extends almost from one end tothe other of the combustion chamber zone z, suitable dead plates 26, 26being arranged at both ends of the air-box 26 to insure a practicallyair-tight `ioint around the upper margins of said air-box so that whensuction is applied thereto the gases from the combustion chamber will bedrawn downwardly through the charge on the pallets I9 into the air-box26. This suction is induced by a blower 29 connected by a. suit-- ableconduit 39 to one side of the air-box 26, said blower also having aconnection with the combustion chamber C adjacent to its discharge endthrough a conduit 3 I. Thus the products of combustion that pass intothe air-box 26 are discharged into the zone z of the combustion chamberC. A second air-box 32 is disposed beneath the chain of pallets I9 andextending substantially throughout the length of the zone z' of thecombustion chamber. The purpose of the second air-box being todistribute a blast of air to the underside of the pallet grates causingsaid air blast to pass upwardly through the grates and the materialthereon into the zone z' of the combustion chamber. A blower 33connected to the air-box 32 by means of a conduit 36 supplies the blastto said air-box. Between the two airboxes 26 and 32 I provide anigniting furnace 36 comprising essentially a closed chamber 36 open atthe tcp in close proximity to the under side of the pallets I9, andslightly beyond the baille b which separates the combustion chamber intothe two zones z and z'. A suitable burner (which is not shown but may besimilar to that described in my co-pending application, Serial No.685,820, led August 19, 1933) feeds a mixture of liquid fuel and air tothe combustion chamber 36, and when the same is ignited said chamber iscompletely filled with flame and hot gases under pressure which forcesthe products of combustion upwardly through the pallet grates intointimate contact with the material thereon whereby said material becomeignited.

In the operation of my invention, the hoppers H and H are charged withmaterial that is to be incinerated. The material m that is charged intothe hopper H is more finely divided than that charged into the hopper H'and is graded so that the particles composing the material will be ofsubstantially uniform size, such that w111 pass a 11/2 screen. Thematerial m charged into the hopper H is not graded and is not of uniformsize but consists of a mixture of rubbish, garbage, broken boxes andpaper. .The bottom of the hopper H is open and the material continuouslydischarges from said hopper onto the grates of the chain of palletswhich comprise the support i for the material as it travels through thefurnace. As thepallets move under the hopper H the bottom edge e of thehopper cuts oiI the ow of material so that it arranges itself in thepallets in the form of a layer (as shown in Fig. 2). The layer of thematerial m is carried through the zone z of the combustion chamber andimmediately after passing the bame b the material m from the hopper H'is charged on top of it. Obviously, the feeding plunger Il is operatedat the proper speed so that the correct amount of material dischargedfrom the hopper H' will be ejected therefrom into the zone z of thecombustion chamber C. When the material comes over the igniting furnace35 the flaming particles and hot gases therefrom will be forced into thebottom surface of the layer of material m, effecting ignition thereoffrom one side to the other. As the pallets travel through the zone z'the combustion of the material m will proceed upwardly through the layerand the heat and flaming particles produced by such combustion will ofcourse ignite the material m' superincumbent thereon. The combustion ofboth components of the material m and m will then continue as thematerial is carried through the zone 2 of the combustion chamber C.Obviously, as the material is consumed the bulk thereof will decreaseuntil nally as the top of the material reaches the discharge end .of thepallets it will be in the condition of a compact, porous mass of cinder.I have founrd in practice that the eilect of the draft through thecombustion chamber C induced by the stack S thereof will draw the namingparticles and the heat of the burning mass rearwardly, as shown by thefeathered arrows (Fig. 2), so that kindling of the mass of material m'in the zone z' will be retarded unless some means is provided forcounteracting the effect of the draft in zone z. I, therefore, havedropped the roof 2 near the feed end of the combustion chamber C closerto the charge of mate` rial and have provided the baille b to create aseparate zone z through which only the layer of the material m passes. Asuction is maintained downwardly through the layer of material m bymeans of the air-box 26 and blower 29, under the influence of which theame and hot gases from the igniter 35 and the combustion of the materialimmediately thereabove are drawn into the zone e, and to a certainextent opposing and counteracting the effect of the draft through thezone z'. 'I'he plain arrows indicate the flow of the gases through thezone z, thus, the flame and heat incident to the ignition of thematerial is held close to the baille b so that by the time the materialmoves any considerable distance into the zone z it will be undergoingrapid combustion. Thus, practically from the very beginning of the zonez the material will be burning, and by the time it reaches the end ofsaid zone will have beenentirely consumed except for the cinder residue.'I'he gases that are drawn through the zone z and into the air-box 26are discharged into the zone z' so that these gases will be subjected tothe intense heat therein and will be completely oxidized. Therefore, anygases that reach the stack S will already have passed through thepurifying heat of the zone z and will be free of any odor.

Another advantage `of the flow of hot gases from the zone z' to the zonez and through the layer of material m is the partial drying and heatingof said layer to facilitate the ignition thereof, and at the same timefurnishing a quick exit from the mass of material at the feed end of the75 zone z' for the large volume of gases given off from this materialimmediately after it is kindled. 'I'he function of the baille b is todeflect the hot gases and flaming particles forced into the material bythe ignition furnace 35 downwardly into close contact with the surfaceof the layer of material m, thus making a more thorough Job of theignition of the material comprising said layer. In other words, thesuction induced by the box 26 cooperates .with the baille b toconcentrate the flame from the ignition furnace in the region of saidbaille so that the material will be thoroughly kindled as it starts onits travel through the zone z'.

After the material has been completely burned the residue is dumpedfroml the pallets into a hopper H", from which point it may betransported or handled as desired.

Having described my invention, I claim:

l. An incinerating furnace having a combustion chamber and a preheatingchamber in alinement and in communication, a traveling grate forming thebottom of said chambers and movable from the preheating chamber throughthe combustion chamber, means for charging material on the grate at theentrance to the preheating chamber, means for charging additionalmaterial thereon at the entrance to the combustion chamber, means in theregion of the junction of the chambers for applying flaming particles tothe material on the grate, means for causing air and hot gases to travelfrom the preheating chamber downwardly through the charge, and means forcausing air to move upwardly through the charge to the combustionchamber.

2. An incinerating furnace having a combustion chamber and a preheatingchamber in alinement and in communication, a traveling grate forming thebottom of said chambers and movable from the preheating chamber throughthe combustion chamber, means for charging material on the grate at theentrance to the preheating chamber.' a baille between the preheatingchamber and the combustion chamber for deflecting the hot gasesdownwardly as they enter the preheating chamber, means for chargingadditional material thereon at the entrance to the combustion chamber,means in the region of the junction of the chambers for applying namingparticles to the material on the grate, means for causing air and hotgases to travel from the preheating chamber downwardly through thecharge, and means for causing air to move upwardly through the charge tothe combustion chamber.

3. An incinerating furnace having an elongated combustion chamber, atraveling grate forming the bottom of said combustion chamber, means forfeeding material onto said grates, means for discharging material fromthe grates, a bame within said combustion chamber, means for applyingflaming particles to the material in the region of the baule, means fordrawing hot gases downwardly through the material between the feedingmeans and the baille, and means for passing air upwardly through thematerial between the baille and the discharge means.

4. An incinerating furnace having an elongated combustion chamber, atraveling grate forming the bottom of said combustion chamber, means forfeeding material onto said grate,

means for discharging material from the grate, a baille within saidcombustion chamber, means for forcing hot gases and flaming particlesupwardly into the material in the region of the baffle, means fordrawing hot gases downwardly through the material between the feedingmeans and the baille, and means for passing air upwardly through thematerial between the bafiie and the discharge means.

5. A furnace comprising a combustion chamber and a pervious supportforming the bottom of said chamber, means for charging material ontosaid support, means for discharging material therefrom, means for movingsaid support through the combustion chamber, a baille in the combustionchamber forming a narrow passage between its lower edge and the materialsupport, an igniter disposed below the pervious support and arranged toproject iiaming particles against the charge in the region of thebaille, means for causing a supporter of combustion to traverse thesupport, and means for causing gases to move from the part of thecombustion chamber between the baille and discharge end of the chamberto the part of the combustion chamber between the baille and charge endof the chamber.

6. A furnace comprising a combustion chamber and a pervious supportforming the bottom of said chamber, a baille in said chamber and spacedfrom the pervious support, means at one end of the combustion chamberfor charging material as a layer on said support, means for causing saidsupport to travel beneath said baille, means for charging additionalmaterial on said layer beyond the baille, means for igniting the bottomSurface of the bottom layer in the region of the baille, means forcausing hot gases to pass downwardly through said layer between thecharging end of the chamber and the baille, and means for causing asupporter of combustion to traverse the material beyond the banie.

7. An incinerating furnace having a combustion chamber and a preheatingchamber in alinement and in communication, a traveling grate forming thebottom of said chambers and movable from the preheating chamber throughthe combustion chamber, means for charging material on the grate at theentrance to the preheating chamber, means for charging additionalmaterial thereon at the entrance to the combustion chamber, means in theregion of the junction of the chambers for applying flaming particles tothe material on the grate, means for exhausting the hot gases from thepreheating chamber, and means for causing air to move upwardly throughthe charge to the combustion chamber.

8. An incinerating furnace having an elongated combustion chamber, atraveling grate forming the bottom ot said combustion chamber, means forfeeding material onto said grate, means for discharging material fromthe grate. means for forming an auxiliary chamber within the combustionchamber near the feed end thereof, means for applying flaming particlesto the material as it leaves the auxiliary chamber, means for passingair upwardly through the material in the combustion chamber, and meansfor maintaining an independent draft through the auxiliary chamber.

JOHN E. GREENAWALT.

